<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>demo 2-5</title>
	</head>
	<body>
	</body>
	<script>
		function fun(){
			let n = 'a';
			if(true){
				let n = 'b';
			}
			console.log(n);
		}
		fun();
	</script>
</html>